Great question! I've wondered this myself, and am currently trying to do a slow-burn gain after a big rapid one. I'll let you know if I see a difference

My guess, however, is that by the end of that year they'd look the same. My body shape changes while I'm gaining- bigger, puffier belly, for sure- but as the weight settles on me during the few months after, it winds up going to all the usual places- thighs, bum, then belly, and general additions everywhere else.
I think the culprit if a couple things. 1- bingeing causes bloating, 2- bingeing causes the stomach and muscles to expand, but they bounce back over time. And 3- skin takes time to stretch and accommodate new fat. The biggest thing I've noticed is how firm my fleshy bits feel when I'm gaining, and how soft and jiggly I feel once I'm maintaining or losing. That says skin elasticity is a factor, too.